glibc/iconv/gconv_open.c

209 lines
5.7 KiB
C

/* Find matching transformation algorithms and initialize steps.
Copyright (C) 1997-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <locale.h>
#include "../locale/localeinfo.h"
#include <stdlib.h>
#include <string.h>
#include <gconv_int.h>
int
internal_function
__gconv_open (const char *toset, const char *fromset, __gconv_t *handle,
int flags)
{
struct __gconv_step *steps;
size_t nsteps;
__gconv_t result = NULL;
size_t cnt = 0;
int res;
int conv_flags = 0;
const char *errhand;
const char *ignore;
bool translit = false;
/* Find out whether any error handling method is specified. */
errhand = strchr (toset, '/');
if (errhand != NULL)
errhand = strchr (errhand + 1, '/');
if (__glibc_likely (errhand != NULL))
{
if (*++errhand == '\0')
errhand = NULL;
else
{
/* Make copy without the error handling description. */
char *newtoset = (char *) alloca (errhand - toset + 1);
char *tok;
char *ptr = NULL /* Work around a bogus warning */;
newtoset[errhand - toset] = '\0';
toset = memcpy (newtoset, toset, errhand - toset);
/* Find the appropriate transliteration handlers. */
tok = strdupa (errhand);
tok = __strtok_r (tok, ",", &ptr);
while (tok != NULL)
{
if (__strcasecmp_l (tok, "TRANSLIT", _nl_C_locobj_ptr) == 0)
translit = true;
else if (__strcasecmp_l (tok, "IGNORE", _nl_C_locobj_ptr) == 0)
/* Set the flag to ignore all errors. */
conv_flags |= __GCONV_IGNORE_ERRORS;
tok = __strtok_r (NULL, ",", &ptr);
}
}
}
/* For the source character set we ignore the error handler specification.
XXX Is this really always the best? */
ignore = strchr (fromset, '/');
if (ignore != NULL && (ignore = strchr (ignore + 1, '/')) != NULL
&& *++ignore != '\0')
{
char *newfromset = (char *) alloca (ignore - fromset + 1);
newfromset[ignore - fromset] = '\0';
fromset = memcpy (newfromset, fromset, ignore - fromset);
}
/* If the string is empty define this to mean the charset of the
currently selected locale. */
if (strcmp (toset, "//") == 0)
{
const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
size_t len = strlen (codeset);
char *dest;
toset = dest = (char *) alloca (len + 3);
memcpy (__mempcpy (dest, codeset, len), "//", 3);
}
if (strcmp (fromset, "//") == 0)
{
const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
size_t len = strlen (codeset);
char *dest;
fromset = dest = (char *) alloca (len + 3);
memcpy (__mempcpy (dest, codeset, len), "//", 3);
}
res = __gconv_find_transform (toset, fromset, &steps, &nsteps, flags);
if (res == __GCONV_OK)
{
/* Allocate room for handle. */
result = (__gconv_t) malloc (sizeof (struct __gconv_info)
+ (nsteps
* sizeof (struct __gconv_step_data)));
if (result == NULL)
res = __GCONV_NOMEM;
else
{
/* Remember the list of steps. */
result->__steps = steps;
result->__nsteps = nsteps;
/* Clear the array for the step data. */
memset (result->__data, '\0',
nsteps * sizeof (struct __gconv_step_data));
/* Call all initialization functions for the transformation
step implementations. */
for (cnt = 0; cnt < nsteps; ++cnt)
{
size_t size;
/* Would have to be done if we would not clear the whole
array above. */
#if 0
/* Reset the counter. */
result->__data[cnt].__invocation_counter = 0;
/* It's a regular use. */
result->__data[cnt].__internal_use = 0;
#endif
/* We use the `mbstate_t' member in DATA. */
result->__data[cnt].__statep = &result->__data[cnt].__state;
/* The builtin transliteration handling only
supports the internal encoding. */
if (translit
&& __strcasecmp_l (steps[cnt].__from_name,
"INTERNAL", _nl_C_locobj_ptr) == 0)
conv_flags |= __GCONV_TRANSLIT;
/* If this is the last step we must not allocate an
output buffer. */
if (cnt < nsteps - 1)
{
result->__data[cnt].__flags = conv_flags;
/* Allocate the buffer. */
size = (GCONV_NCHAR_GOAL * steps[cnt].__max_needed_to);
result->__data[cnt].__outbuf = malloc (size);
if (result->__data[cnt].__outbuf == NULL)
{
res = __GCONV_NOMEM;
goto bail;
}
result->__data[cnt].__outbufend =
result->__data[cnt].__outbuf + size;
}
else
{
/* Handle the last entry. */
result->__data[cnt].__flags = conv_flags | __GCONV_IS_LAST;
break;
}
}
}
if (res != __GCONV_OK)
{
/* Something went wrong. Free all the resources. */
int serrno;
bail:
serrno = errno;
if (result != NULL)
{
while (cnt-- > 0)
free (result->__data[cnt].__outbuf);
free (result);
result = NULL;
}
__gconv_close_transform (steps, nsteps);
__set_errno (serrno);
}
}
*handle = result;
return res;
}